Nine identical cubes, each with edge 3 cm, are joined in a straight line to form a cuboid. What is the total surface area (in cm²) of the resulting cuboid?

Correct option is A

Given:
Number of cubes = 9
Edge of each cube (a) = 3 cm
Formula Used:
TSA of cuboid = 2(lb + bh + hl)
Solution:
When 9 cubes are joined in a line:
Length (l) = 9 \times 3 = 27 cm
Breadth (b) = 3 cm
Height (h) = 3 cm
TSA = $$2(27 \times 3 + 3 \times 3 + 3 \times 27)$$​​
TSA = 2(81 + 9 + 81) = 2(171) = 342 cm²
So the correct answer is (A).